Secure and efficient information sharing has been a longstanding problem in many contexts.
Sharing “too freely” results in information leakage. Yet, not sharing enough results in a failure to ‘connect the dots’. Even if information leakage is not the concern, overly free sharing of information results in information overload. Various solutions to these problems have been proposed, yet the problems persist. Before turning our attention to our new solution to this old problem, let us consider the two broad methods of information sharing currently prevalent.
In the first category are the “information push approaches. Email, instant messengering, voice mail, texting are examples of information push. Some of the key features are:                TELLING (Alice feels Bob needs to know)        ASKING (Alice can query Bob or a group)        Expectation (justified or not) of PRIVACY        Loss of CONTROL of information spread        Not well suited for SEARCHING and FINDING        No LENDING (limited duration sharing)        REVOCATION (UNsharing) is usually hard to enforce        MONITORING is possible, but not integral,        
In the second category are what we term the “publish and subscribe” model. Social networks, listservs, wikis, blogs, microblogs are example of this model. Some of the key features are:                TELLING and ASKING happen; but without expectation that “correct” person will receive the th question or the answer        SEARCHING and FINDING are fundamental        Low expectation of PRIVACY        Significant loss of CONTROL of information spread        No LENDING (limited duration sharing)        REVOCATION (UNsharing) is usually hard to enforce        MONITORING is possible, but not integral        
Neither model has been successful in optimal information sharing. The end result is still either too little sharing and a resultant failure to connect the dots, or else too much sharing resulting in information leakage and information overload.
Rely on human judgement on what to share with whom. Can be over-ridden by policies but is not driven by policies such as “all people at this level can see”, or, “prove that there is a need to know”.